SSM opens the door to numerous scenarios and yes green cards, visas, etc.. will be amongst them, as before. However SSM will definitely open the door to enhanced paedophilic activity and other very unusual monetary/legal connotations not yet even thought of.

As SSMs cannot be consummated they cannot be annulled, nor will adultery be applicable as a reason to divorce, hence all the civil marriage laws will need to change to accommodate this.

It's all completely farcical. SS relationships could have been fully catered for through type, i.e. hetero or SS.
civil partnership agreements, with specific criteria used depending on the partnership